Leiden University: A ‘lock’ to make genetic modification safer
What if we could modify small organisms to make them gorge on CO2? Or extract nitrogen from the air and convert it into fertiliser? This would enable us to make these organisms into smart allies in the nitrogen crisis or in the fight against climate change.
The potential of this kind of genetically modified organism (GMO) has not been fully realised, says the Leiden team that is entering the iGEM student competition this year. The danger of genetic modification is that the organisms could enter the wild and outcompete the organisms there. To prevent this GMOs are only permitted under strict conditions.
The Leiden student team wants to change this and has therefore developed a ‘lock’ that will make GMOs safer to use. They are producing their Double Plasmid Lock (DOPL LOCK for short) for the international iGEM biology competition. They recently launched a crowdfunding campaign so that they can further develop this innovation.
‘Our idea is to distribute the artificial genetic material of a GMO between two separate pieces of circular DNA, also known as plasmids,’ says Iris Noordermeer, who is doing a master’s in Molecular Genetics and Biotechnology. ‘We give each plasmid its own toxin. By equipping each plasmid with the other’s antitoxin, we ensure that the cell only remains alive if the plasmids are together. This means that an individual plasmid can’t be transferred to another bacteria.’
This lock should therefore make it impossible for GMOs to enter the wild. The plasmids hold each other captive in a tight embrace, Noordermeer explains. ‘That’s why we also call our double safety system a Romeo and Juliet model: one plasmid can’t survive without the other.’
Last year a Leiden student team won the iGEM competition with their test kit for infectious diseases, a fantastic achievement. This year’s entry might be less spectacular but it is equally important, says Chanel Naar, who is doing a master’s in Biomedical Sciences. ‘Our lock might not be a sexy topic that will result in a publication in Nature. But it’s badly needed nonethless because it will mean that other researchers can make safe use of genetic modification, which will bring numerous interesting applications within reach.’